This invention relates to seals and more particularly to a shaft seal having end faces free from contact with adjacent structure.
Many seal configurations are available for sealing against a rotating or sliding shaft for retaining liquids within a chamber housing a bearing while excluding extraneous material. In most cases a lubricant is necessary for proper sealing action between the seal and the shaft, such lubricant normally being supplied from within the chamber. In the case of nonlubricated or dry running bearings where lubricants are not present, it is still desirable to have a seal to protect these bearings from abrasive material to prolong their operational life. Such a seal should have good abrasive resistant qualities and in many applications must be capable of sustaining radial shaft deflections. Furthermore, since those seals are subjected to greater wear, particularly the outer edges thereof, it is desirable for them to have the ability to deform radially for maintaining intimate sealing contact with the mating surface as wear occurs. Moreover, since the outer edges of such seals usually wear more rapidly than the mid portion of the seal, it is also desirable to have means for compensating for the greater amount of wear at the outer edges and for maintaining high localized unit load at the outer edges.